Screen printers, tensile screens and masks are some of the ways used to pattern a variety of aesthetic and circuit layouts. Screen printers require screens to pattern which can be costly and use excess material. Changing patterns can only be done by making unique screens for each pattern. There are significant materials that have been developed for screen printing, however, there is a range of material properties that works well for screen printing, but these must be tightly controlled for repeatable results. The advantage of these is the speed at which a pattern can be printed; screen printers are the industry standard for high speed or large volume. The disadvantage is the need for a flat surface and screen printing is limited to low aspect ratio features and cannot produce 3D builds.
There is a need for a method to produce patterns on flat or conformal surfaces and to add multiple layers on those surfaces for high speed patterning of single materials, high speed patterning of multiple materials and high speed layering for 3D builds. Adding layers is known as additive manufacturing and is an established industry with a number of additive techniques. Standard stereolithography uses a vat of polymer material and focuses a laser on the surface of the vat and polymerizing the polymer material via Ultra Violet (UV) curing process. One technique to allow for multiple materials is to use multiple vats, which is cumbersome. Additional techniques such as ink jetting a thin UV polymer does allow for multiple material additive building; the limitation to this approach is the limited material choices; ink jettable material must be a low viscous material with low to no particle loading. An extrusion method called Fused Deposition Modeling uses a heated nozzle and pushes a plastic or metal wire through to build 3D shapes. The limitation here is the requirement for heat to melt the plastic or metal wire before extrusion.
Therefore, despite various approaches available, problems remain.